1. Field of the Invention
This invention relates to optical fiber centering devices and, in particular, to such devices which provide alignment of an optical fiber with high accuracy so as to be suitable for use in numerous fiber coupling designs. Accordingly, it is a general object of this invention to provide new and improved devices of such character.
2. Description of the Prior Art
Various techniques were used in the past to center optical fibers. Such techniques, as known, utilized either (1) micromanipulators to initially align an optical fiber either manually or servomechanically before applying epoxy to fix the fiber in place; (2) precision machined holes, or ferrules, in conjunction with epoxying, soldering or crimping; or (3) watch jewels, often requiring several in tandem, followed by epoxying or crimping.
In the foregoing methods, highly accurate, usually expensive parts were required. Micromanipulators, however, could be used only in a laboratory environment or its equivalent. Human or servomechanical adjustment was required and the optical fiber had to be held precisely in place during the epoxy curing time. Machined metal parts used in some connectors required extreme machining accuracy and hence, were expensive to use. Machined holes and jewels had to be sufficiently large to accept all fiber diameters within a manufacturer's tolerance range, and, therefore, tended to be loose fits for most fibers.
3. Discussion of Other Art
In two copending United States patent applications, one by W. John Carlsen entitled "METHODS OF AND APPARATUS FOR CONNECTING OPTICAL FIBERS", Ser. No. 23,862, filed Mar. 26, 1979, now U.S. Pat. No. 4,325,607, issued Apr. 20, 1982, and the other by W. Griffin, W. John Carlsen and J. E. Benasutti entitled "ELASTOMERIC FIBER OPTIC SPLICE", Ser. No. 32,583, filed Apr. 23, 1979, now U.S. Pat. No. 4,257,674, issued Mar. 24, 1981, there are described fiber optic splices which were designed to precisely align automatically two fibers along the same axis so as to optimize power transfer between them. The instant invention, however, is intended to precisely align a single fiber automatically along an externally defined axis.
In a third copending United States patent application by W. John Carlsen entitled "OPTICAL FIBER CONNECTORS", Ser. No. 112,991, filed Jan. 17, 1980, there is described telecentric fiber optic connectors using plastic molded optics. Alignment is achieved by utilizing a variation of the splice configuration shown in the Ser. No. 23,862 application, wherein accuracy of the mold and molding process provide a precise centering.